1. Field of the Invention
The present invention is directed generally to microelectronics and more specifically to a microelectronic circuit structure and method for manufacturing same.
2. Description of the Related Art
In semiconductor technology, microelectronic components and circuits are defined in the lateral direction by insulation structures and/or potential barriers. The possibilities for miniaturizing these components and circuits are therefore linked to the fineness that can be achieved in the structuring methods used for manufacturing insulation structures and potential barriers.
This is true for both conventional components such as, for example, MOSFETs or MODFETs as well as for new component designs of nanoelectronics. Quantum-mechanical effects are utilized in these components of nanoelectronics at dimensions around 10 nm (see, for example, K. K. Likharev et al, Spektrum der Wissenschaft, August 1992, pages 62-67 and E. Corcoran, Spektrum der Wissenschaft, January 1991, pages 76-86). Conductive boundary surface or quantum well channels are generated in semiconductor structures by lateral structuring, wherein two-dimensional electron or hole gases form. These are quantized in a vertical direction. A lateral quantization is added given further miniaturization of the dimensions, as a result whereof quantum wire or quantum dot structures occur. Also, quantum-mechanical tunneling through thin, lateral potential barriers that are arranged between neighboring structures are also utilized in nanoelectronics.
For lateral structuring of semiconductors, it is known to utilize lithography methods in combination with corresponding structure transfer methods. The most significant structure transfer methods are layer deposition, etching methods and doping methods. X-ray, electron and ion beam lithography are mainly employed for producing structures having lateral dimensions below 0.1 .mu.m. Structures down to 30 nm can be produced with electron beam lithography. The suitability of lithography, deposition and surface modification methods using scanning, tunneling microscopes and atomic force microscopes for achieving even smaller structures is the subject of investigations (see, for example, M. A. McCord et al, J. Vac. Sci. Tech. Vol. 4 (1) pages 86-88 (1986); and G. Binnig et al, Phys. Rev. Lett. 56, pages 930 f (1986).
In addition to being limited by the resolution of the lithography used, the structural fineness is limited by regions in the semiconductor produced by doping in that implantation regions in the semiconductor diverge in the required activation by curing.